Currently, there are numerous Top of Rack (ToR) access devices in a data center. The deployment of 10-Gigabit servers is a gradual process. It is common to construct a network with a mix of Gigabit servers and 10-Gigabit servers. How to simplify the network structure and management is one issue and some data center technologies aim to achieve functions such as a single management domain, reducing network hierarchies, and flattened management by use of a virtualization access network.